We keep asking why the average individuals mental health is on the decline and this is a big part of it.
Some of us have been doing this since we were children, replacing work with school. The only way you can manage all of this is by multitasking everywhere possible. You only socialize while at work or school, and all the while you're probably either working on something or you're on your phone. You clean and tidy at the same time as you cook. You speedrun your showers, a time that should be somewhat relaxing.
Even assuming you do actually get those full precious 8 hours of sleep, your brain isn't going to be rested enough.